It is best to check Google Maps the day you plan on leaving. The distance is about equal, but there are three lanes on I15, only 2 lanes on most of I215. At the 215/60 interchange, it can have REALLY bad traffic from 6 am to 10 am, and most afternoons and Sunday afternoons.
You can also check google maps, change the time to "Tuesday" and it will give you an average traffic report for that day of the week, based on the time you also can select. The green lines are more than 45 MPH, yellow below 45, red below 25 and black dash red is 0-15 mph on the freeways.
Good luck,
Fred.
PS: I would take I 15 from SD to Victorville.
